White dwarf cooling sequences and cosmochronology

The evolution of white dwarfs is a simple gravothermal process. This means that their luminosity function, i.e. the number of white dwarfs per unit bolometric magnitude and unit volume as a function of bolometric magnitude, is a monotonically increasing function that decreases abruptly as a consequence of the finite age of the Galaxy. The precision and the accuracy of the white dwarf luminosity functions obtained with the recent large surveys together with the improved quality of the theoretical models of evolution of white dwarfs allow to feed the hope that in a near future it will be possible to reconstruct the history of the different Galactic populations.Comment: Proceedings of the 40th Liege International Astrophysical Colloquium: Aging low mass stars: from red giants to white dwarf

La Iglesia y el Evolucionismo: El caso de Raffaello Caverni

SUMARIO: 1. LOS PROCEDIMIENTOS DE LA CONGREGACIÓN DEL ÍNDICE. 2. UN PECULIAR CURA DE PUEBLO. 3. LOS NUEVOS ESTUDIOS DE FILOSOFÍA. 4. LA RESEÑA DE «LA CIVILTÀ CATTOLICA». 5. UN TRATADO EN ENTREGAS. 6. LA DENUNCIA DEL ARZOBISPO. 7. UN INFORME DE LUJO. 8. EL INFORME DE ZIGLIARA SOBRE EL LIBRO DE CAVERNI. 9. SE PROPONE PROHIBIR EL LIBRO. 10. LA CONGREGACIÓN PREPARATORIA DEL 27 DE JUNIO DE 1878. 11. LA CONGREGACIÓN GENERAL DEL 1 DE JULIO DE 1878. 12. LA AUDIENCIA PAPAL Y LA PROMULGACIÓN DEL DECRETO. 13. REACCIÓN DE CAVERNI. 14. EL SIGNIFICADO DE LA CONDENA «INDIRECTA»

Directional cue and landmark configurations: The effect of rotating one set of landmarks relative to another

This is the author accepted manuscript. The final version is available from the American Psychological Association via the DOI in this recordIn this article we addressed the question whether rats can use distal landmarks as directional cues that are used in combination with other proximal landmark configurations. The animals were trained with an A, B, C, and D landmark configuration in the Morris pool, where B and C are the near (to platform) landmarks and A and D the far ones. We also added another more distal "directional" cue Z (a white strip attached to the black curtain surrounding the pool). Experiment 1 shows a robust detrimental effect on the time spent by the rats swimming in the platform quadrant when the location of all landmarks was "Inverted" (rotated by 180 degrees) with respect to Z. A similar detrimental effect was found when, after the inversion manipulation, the locations of the near and far landmarks were "Flipped" (B swapped with C and A with D). Rats in both Inverted and Flipped tests spent more time in the Z quadrant compared to the platform quadrant (BC). Experiment 1b provided evidence distinguishing between alternative explanations of how the directional cue Z acts in combination with the other landmarks. The results from both experiments show that Z operates differently to the standard landmarks. It can function as a beacon in its own right. It can also combine with the other landmarks to produce a high level of search performance, in a way that we hypothesize to be distinct from that described by the configural analysis often applied to multiple landmarks.European Union Horizon 2020Economic and Social Research Council (ESRC

DC-Gain Measurement of the Frequency-to-Output Power Transfer Function based on sidebands for Domestic Induction Heating Applications

This paper analyzes different alternatives to obtain the dc gain of the frequency-to-output power transfer function of a series half-bridge resonant inverter for domestic induction heating. In this application, a full-wave rectified bus voltage usually feeds the inverter, and a constant switching frequency is applied during each half-period of the mains voltage. This dc gain is the derivative of the output power with respect to the frequency. A finite difference approximation to the derivative can be obtained measuring the output power during two consecutive half-periods of the mains voltage by injecting a small frequency increment in the second one. This paper compares five alternatives to estimate the gain in only one half-period of the mains, what would allow to increase the controller bandwidth. The alternatives are based on the computation of the DTFS of the sidebands. They are off-line implemented and experimentally verified. The proposed method can also be implemented in real time into a digital controller

An amplifier-less acquisition chain for power measurements in series resonant inverters

Successive approximation register (SAR) analog-to-digital converter (ADC) manufacturers recommend the use of a driver amplifier to achieve the best performance. When a driver amplifier is not used, the conversion speed is severely penalized because of the need to meet the settling time constraint. This paper proposes a simple digital correction method to raise the performance (conversion speed and/or accuracy) when the acquisition chain lacks a driver amplifier. It is intended to reduce the cost, size and power consumption of the conditioning circuit while maintaining acceptable performance. The method is applied to the measurement of the output power delivered by a series resonant inverter for domestic induction heating

Séneca el Viejo y Quevedo

En este artículo se revisa la influencia de las Controversias y Suasorias de Séneca el Viejo en la obra de Francisco de Quevedo. Se analiza en primer lugar la traducción que hizo Quevedo de las suasorias 6 y 7 y la incorporación de dicha versión como apéndice a su Vida de Marco Bruto. Una segunda parte se centra en la traducción quevediana, recientemente descubierta, de algunas controversias. En ambas secciones se pone de manifiesto que Quevedo no se limitó a traducir —en una búsqueda deliberada de literalidad— el texto latino, sino que introdujo además su propia recreación del modelo senequiano. Finalmente, se indagan algunas razones del interés de Quevedo por la obra de Séneca el Viejo y se apuntan, como posibles elementos de atracción, la brevedad y concisión de las sententiae senequianas y muy especialmente la acumulación estática de frases que las caracteriza

The histidine phosphocarrier kinase/phosphorylase from bacillus subtilis is an oligomer in solution with a high thermal stability

The histidine phosphocarrier protein (HPr) kinase/phosphorylase (HPrK/P) modulates the phosphorylation state of the HPr protein, and it is involved in the use of carbon sources by Gram-positive bacteria. Its X-ray structure, as concluded from crystals of proteins from several species, is a hexamer; however, there are no studies about its conformational stability, and how its structure is modified by the pH. We have embarked on the conformational characterization of HPrK/P of Bacillus subtilis (bsHPrK/P) in solution by using several spectroscopic (namely, fluorescence and circular dichroism (CD)) and biophysical techniques (namely, small-angle X-ray-scattering (SAXS) and dynamic light-scattering (DLS)). bsHPrK/P was mainly a hexamer in solution at pH 7.0, in the presence of phosphate. The protein had a high conformational stability, with an apparent thermal denaturation midpoint of ~70¿ C, at pH 7.0, as monitored by fluorescence and CD. The protein was very pH-sensitive, precipitated between pH 3.5 and 6.5; below pH 3.5, it had a molten-globule-like conformation; and it acquired a native-like structure in a narrow pH range (between pH 7.0 and 8.0). Guanidinium hydrochloride (GdmCl) denaturation occurred through an oligomeric intermediate. On the other hand, urea denaturation occurred as a single transition, in the range of concentrations between 1.8 and 18 µM, as detected by far-UV CD and fluorescence

Vessel Recognition in Induction Heating Appliances - A Deep-Learning Approach

The selection of a vessel by an induction-hob user has a significant impact on the performance of the appliance. Due to the induction heating physical phenomena, there exist many factors that modify the equivalent impedance of induction hobs and, consequently, the operational conditions of the inverter. In particular, the type of vessel, which is a sole decision of the user, strongly affects these parameters. Besides, the ferromagnetic properties of the different materials the vessels are made with, vary differently with the excitation level, and given that most of the domestic induction hobs are based on an ac-bus voltage arrangement, the excitation level continuously varies. The algorithm proposed in this work takes advantage of this fact to identify the equivalent impedance of the load and recognize the pot. This is accomplished through a phase-sensitive detector that was already proposed in the literature and the application of deep learning. Different convolutional neural networks are tested on an augmented experimental-based dataset and the proposed algorithm is implemented in an experimental prototype with a system-on-chip. The proposed implementation is presented as an effective and accurate method to characterize and discriminate between different pots that could enable further functionalities in new generations of induction hobs